README.list

These routines perform operations on two types of lists. One is a
generic list (list_* routines) and one is a string integer list (sl_*
routines).
The list routines work on a string containing a comma-separated list.
They break it down and return the elements of the list one at a time.
The string integer list routines perform operations on a string containing
a list of numbers. A list is of the format "1,3-4,7,9,12-13". There
are no spaces allowed, and the list may only contain positive integers
(or zero).
The following routines return the next element in the list as a string
(list_XXX_ele), an integer (list_XXX_int), or a real (list_XXX_num).
For example:
str='abc,123,34.5'
ptr=0
call list_next_ele(str,ptr,ele,err) => ele='abc'
call list_next_int(str,ptr,int,err) => int=123
call list_next_int(str,ptr,int,err) => int=0,err=1,ptr=unchanged
call list_next_num(str,ptr,num,err) => num=34.5
call list_next_ele(str,ptr,ele,err) => ele='',err=-1
There is a potential problem with many of the subroutines. The value of
err could be different from zero if a value from previous call is passed
in even though the result should be 0. Err must be set to 0 at the
beginning of each subroutine, or use a different variable in the main
program.
Some problems have been fixed. SI, 4/98